Furnace-grate and shaker therefor



(No Model.)

1-] MATHER PURNAOB GRATE AND SHAKER THEREFOR.

Patented Aug. 12, 1890.

2 f avLwm Coz- 3294 9 14 Que MAO I UNITED STATES PATENT OFFICE.

EDMUND MATHER, OF HARRISBURG, PENNSYLVANIA.

FURNACE-GRATE AND SHAKER THEREFOR.

SPECIFICATION forming part of Letters Patent No. 433,952, dated August 12, 1890.

' Application filed April 29, 1890. Serial No. 349,920. (No model) To all whom it may concern.-

Be it known that I, EDMUND h/IATHER, of Harrisburg, in the county of Dauphin and State of Pennsylvania, have invented certain new and useful Improvements in Furnace- Grates and Shakers Therefor; and I do hereby declare the following to be a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming a part of this specification, and to the letters of reference marked thereon.

This invention relates particularly to that class of grates ordinarily employed in connection with steam-boilers and employing a series of parallel grate-bars carried by bearingbars supported by the wall of the fire-box.

In the practical operation of grates such as above mentioned, particularly if culm or waste be burned thereon, it is found that the most economical and best results are obtained if a solid bed of live coals is maintained on the grate with the live coals exposed to the air both above and below or in the fire-box and ash-pit respectively. Ordinarily the accumulation of ashes in the bottom of the bed of coals, as well as the clinkers, slate, and other non-combustible accumulations, are removed by a process commonly known as cleaning-that is to say, a poker or stoking-bar is introduced and passed around through the body of incandescent fuel, the ashes being thereby shaken through the grate and the clinkers and non-combustible accumulations being drawn out through the fire. It is found necessary in the practical operation of all steam-boiler furnaces of this class to clean more or less frequently, to remove the clinkers, slate, and other accumulations mentioned, which while in small quantities do not mas terially affect the efficiency of the furnace if the accumulation of fine ashes is removed, would, if allowed to accumulate to any great extent, practically choke up the furnace, to say nothing of other incidental damage. Every time the bed of incandescent fuel is broken up in the process of cleaning or otherwise it occasions a proportionate loss in the efficiency of the furnace, due not only to the breaking up of the body of fuel, but also to the admission of a large quantity of cold air above the fire, and, while I do not propose is the object of my invention to render the cleaning practically unnecessary, save at long intervals, by effectually removing the accumulation of fine ashes from the bottom of the bed of fire without breaking the bed of incandescent fuel in the least, thereby leaving the interstices in and to the same free and unobstructed for the passage of the air and gases which support combustion and generate the heat. i

A further object of the invention is to provide means for accomplishing the desired end which shall be capable of application to furnaces now in use without material alteration thereof, permitting the ordinary grate-bars to be employed and necessitating no alteration of the wall of the fire-box at all, thereby reducing the cost of application to the minimum.

To the above ends the invention consists in certain novel details of construction and combinations and arrangements of parts to be hereinafter described, and pointed out particularly in the claims at the end of this specification.

Referring to the accompanying drawings, Figure 1 is a perspective view of a section of a grate constructed in accordance with my invention, sections being broken away to show underlying parts. Fig. 2 is a similar view of one of the bearing-bars, Fig. 3 is a similar View of one of the rocker-bars. Fig. 4 is a section showing operating mechanism, and Fig. 5 is a perspective of the under side of one of the grate-bars having projections attached thereto.

Similarletters of reference in all the figures denote the same parts.

The grate-bars form no part of my present invention, and therefore I have deemed it best to show the invention as applied to and used in connection with a common and wellrecognized form. In the drawings, A indicates one of said grate-bars exactly similar in all respects to those commonly employed in steam-boiler furnaces, and having the openings a through the same for the passage of air, 850., and just inside of the shoulders against which the bearing-bar rests having notches or depressions a cut therein, as shown in Fig. 4:, for a purpose to presently appear. Each alternate bar has these notches or depressions a, and the intermediate bars are provided'with extensions or downward prolongations b, fastened by rivets or otherwise, where old bars are employed, and cast directly on the bars where they are made especially for this use, each having a recess or depression b in the end corresponding to the recess or depression a, in the adjacent bars.

. The bearing bars G are supported by the walls of the fire-chamber, either by being built into the same or carried by brackets secured thereon, and each is formed by two side rails or sides, indicated by the letter C, inclined toward each other, or more properly spread apart at the bottom so as to give suf-' ficient clearance for the ashes and to permit the rocking bars to have a wide range of movement, and connected by cross pieces or webs a suitably spaced, and having bearings c therein. The grate-bars rest over the bearing-bars, and the notches a b are engaged by the oppositely-arranged cranks or cranked rocker-bars E, (shown in perspective in Fig. 3,) which works in the bearings c of the bearing-bar, and when the rocking bar is oscillated the grate-bars are given a similar movement longitudinally without changing to any material degree the level of their upper surfaces, and consequently not breaking up the bed of incandescent fuel in the least, butat the same time effectually remove the accumulation of fine ashes immediately over the gratebars. The cranks on the rocking bar are so proportioned as to each accommodate one grate-bar, and as they project in opposite directionsz'. 6., up and down-the adjacent bars will be moved in opposite directions.

The journals for co-operation with the bearings c are formed by the under side of the upwardly-projecting cranks, the parts being so proportioned as that each grate-bar will engage therewith at exactly the same distance from the center of oscillation, and thereby balance each other should the weight of the superposed fuel tend to move the same.

It will be seen by an inspection of Fig. 4 that the upper surfaces of the cranks are made curved and the bottom of the depressions straight. Thus when the whole weight of the grate-bars rests thereon the grate-bars will not be moved vertically during the reciprocations, as each portion of the curved surface is equidistant from the center of oscillation.

By constructing the bearing-bar open and downward extension D, having an aperture d therein, and a lug d for the attachment of the oscillating mechanism, which consists simply of a handle-bar F inserted in the aperture d of the front bar, and a connecting-rod f joining the lugs d of the front and rear bars, whereby both are oscillated simultaneously when the'handle is operated. Where the firechamber is very wide-say sixty inches-I prefer to employ two rocker-bars at each end, making each bar thirty inches long with the operative faces of adjacent cranks fourinches apart. From this it will be seen that the throw of the cranks is very small, and in practice it is found necessary to leave but a three-fourths-inch space between the ends of the grate-bars and dead-plate in front and bridgewall in rear, and by spreading the side pieces apart at the bottom ample room is afforded for the movement of the lower cranks and extension D. lVhen at rest, with the cranks vertically disposed,the grate is adapted for use as an ordinary stationary grate-bar grate, the'reciprocating mechanism performing no function, and hence the fire may be cleaned in the ordinary manner. The reciprocating mechanism may be applied to any ordinary grate now in use at but very slight cost, it only being necessary to alter the gratebars, as described, and substituting my bearing-bars and rocker-bar for those formerly used, and in the manufacture of the grate and bars designed especially for use in accordance with this invention the increased cost practically amounts to nothing.

In practical operation it is found that a grate constructed in accordance with this invention needs cleaning but twice a day-that is to say, at morning and evening-care being taken in the meanwhile to remove the accumulation of time ashes by operating the rocking bars, thereby insuring a bright fire at all times.

Having thus described my invention, what I claim as new is- 1. In a furnace-grate, the combination, with the parallel grate-bars, of the rocking bar having oppositely-arranged cranks engaging adjacent grate-bars, and the bearing-bars extending across beneath the grate and having end and intermediate bearings therein for the rocking bars, substantially as described.

2. In a furnaccgrate, the combination, with the bearing-bars extending across beneath the grate and having the longitudinal end and intermediate bearings, and the rocking bars journaled in said bearings and having the oppositely-arranged cranks, of the gratebars rcstingon said cranks and adapted to be moved thereby, substantially as described.

3. In afurnace-grate, the combination, with the bearing-bars having the sides and c011- nectingwebs with bearings therein, and the rocking bar having oppositely arranged cranks and j ournaled in said bearings, of the grate-bars resting on said rocking bar and adapted to be moved thereby, substantially as described.

at. In a furnace-grate, the combination, with the bearing-bars having the Web with bearings therein, of the'rockingbar having oppositely-arranged cranks with the journals for co-operation with the bearings in the webs formed on the under surface of the upwardlyprojecting cranks, and the grate-bars engaging said cranks and adapted to be moved thereby, substantially as described.

5. In afurnace-grate, the combination, with the bearing-bars having the Webs with bearings thereon, and the rocking bars having oppositely-arranged cranks journaled in said bearings, of the parallel grate-bars having notches or depressions engaging the upwardly-ext-ending cranks, and the alternate grate bars having the downward extensions engagingthe downwardly-extending cranks, substant-ially as described.

6. In a furnace-grate, the combination, with the bearing-bars composed of the sides spread apart at the bottom and the connecting webs having bearings in the top, of the rocking bars having oppositely-arranged cranks j ournaled in said bearings, and the grate-bars engaging said cranks and adapted to be moved thereby, substantially as described.

7. In a f urnace-grate, the combination, with the bearing-bars composed of the sides spread apart at thebottom and the connecting-Webs having bearings in the top, of the rocking bars having oppositely-arranged cranks and a downward extension for the attachment of EDMUND M ATHER.

Witnesses:

WM. B. IRWIN, JoHN E. PATTERSON. 

